Investigation of Jet Mixing Characteristic Using Slotted Rectangular Tabs

Abstract

A jet is a fluid outflow that emerges from any opening like a convergent nozzle. By newlineusing mechanical slotted tabs, passive flow control of jets can be accomplished for a newlinenumber of benefits, including better mixing, reduced noise, and Thrust Vector Control. newlineExperimental analysis of the effect of the slotted rectangular tabs is done for different newlinesubsonic Mach numbers of 0.6, 0.8 and 1.0 as well as for various nozzle pressure ratios newlineof 3, 4 and 5. Three alternative arrangements of rectangular slotted tabs are used in newlinethe study to control the jet flow. The tabs A, B and C (Tab A - Slant Slotted Tab, Tab newlineB - L Bent Slotted Tab, Tab C - Arc Slotted Tab), which have a 7.3% obstruction by newlinedesign, are positioned opposite one another at the exit of a converging nozzle with 13 newlinemm diameter. Numerical investigations for certain preliminary cases were carried out to newlineknow the efficiency of slotted tabs. Numerical investigation for Mach 0.8 is carried out newlineto validate the experimental investigation of the same Mach number, and further studies newlinewere proceeded. The contours were extracted and the flow behaviors were studied. The newlineexamination yields the centerline total pressure profiles and radial total pressure profiles newlinealong and across the jet axis, and the outcomes are evaluated against the uncontrolled newlinejet. The reduction in the percentage of the core length are then derived, which are a newlinedirect measure of the mixing capabilities in jets. The tabbed jet performs better with newlinethe largest percentage of core length reductions since they are discovered to be stronger newlinemixing promoters. For Mach 0.6 jet, the percentage reductions of the core are 82%, 86% newlineand 89% respectively for Tab A, Tab B and Tab C. For Mach 0.8 jet, core reductions newlineare 84%, 89% and 91% respectively for Tab A, Tab B and Tab C. And for Mach 1 newlinejet, the core reductions are 84%, 88% and 91% respectively for Tab A, Tab B and Tab newlineC. Amongst the three configurations, Tab C is seen to be the better performer with newlinepercentage reductions of 89%, 91%, and 91% for Mach 0.6, 0.8, a